Quarterly report pursuant to Section 13 or 15(d)

Debt (Details)

v3.22.2
Debt (Details) - USD ($)
shares in Millions, $ in Millions
6 Months Ended
May 12, 2021
Dec. 18, 2020
Aug. 12, 2020
Jun. 30, 2022
Dec. 31, 2021
2.75% Exchangeable Senior Debentures due 2050          
Debt disclosures          
Carrying value       $ 548.0 $ 585.0
Interest rate (as a percent)       2.75% 2.75%
1.25% Exchangeable Senior Debentures due 2050          
Debt disclosures          
Carrying value       $ 775.0 $ 818.0
Interest rate (as a percent)       1.25% 1.25%
1.75% Exchangeable Senior Debentures due 2046          
Debt disclosures          
Carrying value       $ 19.0 $ 25.0
Interest rate (as a percent)       1.75% 1.75%
Line of credit          
Debt disclosures          
Carrying value       $ 398.0 $ 399.0
SPV | Margin Loan Facility          
Debt disclosures          
Borrowings       300.0  
Repayments of debt       200.0  
Carrying value       $ 1,400.0 $ 1,300.0
Outstanding revolving loans $ 850.0        
Number of business days prior to the maturity date       5 days  
Remaining borrowing capacity       $ 900.0  
SPV | Margin Loan Facility | Charter.          
Debt disclosures          
Number of common shares pledged as collateral       12.3  
Value of pledged collateral       $ 5,700.0  
SPV | Margin Loan Facility | Three-month LIBOR          
Debt disclosures          
Interest rate basis     three-month LIBOR    
Basis spread on variable rate 1.50% 1.85% 1.50%    
SPV | Term loan          
Debt disclosures          
Carrying value $ 1,150.0        
SPV | Revolving Credit Facility          
Debt disclosures          
Maximum borrowing capacity 1,150.0        
Amount outstanding 0.0        
SPV | Uncommitted Incremental Term Loan Facility          
Debt disclosures          
Maximum borrowing capacity $ 200.0